PROGRESS IN GEOGRAPHY ›› 2016, Vol. 35 ›› Issue (1): 98-107.doi: 10.18306/dlkxjz.2016.01.011

• Orginal Article • Previous Articles     Next Articles

Variation of aeolian sediment flux profiles on a parabolic dune at the southern fringe of the Hobq Desert

Binbin TAO(), Dan LIU, Chao GUAN, Eerdun HASI*()   

  1. College of Resource Science and Technology, Beijing Normal University, Beijing 100875, China
  • Online:2016-01-31 Published:2016-01-31
  • Contact: Eerdun HASI;
  • Supported by:
    National Natural Science Foundation of China, No.41171002, No.41271020


The airflow and sediment transport rate on the parabolic dune and the aeolian sediment flux profiles were examined in details in the southern Hobq desert in late April 2010 when the wind was strong and sediment movement was intense. The analyses show that 71%~91% sediments moved in the space between 0 and 0.10 m above surface. This confirms the results of previous research that blown sand activity occurs near bed. Due to the difference of wind velocity, underlying surface conditions, and slope profiles, sediment transport rate and relative sediment transport rate vary, so do the aeolian sediment flux profiles. At the measurement spots where wind velocity and sediment transport rate are small, such as the toe and the lower part of the windward slope, the aeolian sediment flux profiles vary considerably. Underlying surface condition is a vital factor influencing aeolian sediment flux profile. At the windward toe that suffers deflation, the gravelly surface is hard. This contributes to sediments’ saltaltion, so sediment transport rate is relatively high at the upper layer of the aeolian sediment flux profile. Along the windward slope, sediments move upward and have a lower saltation height. Therefore sediment transport is relatively high near surface. In contrast, sediments move downward at brink-line on the leeward slope with higher height and the trajectories deform, so the saltation height is higher. Affected by the difference of windward slope profile shape, the aeolian sediment flux profiles at the crest vary markedly among the measurement spots. In spite of the variation of the aeolian sediment flux profiles, they can still be well described by the exponential decay law at the windward slope and crest. In the equation Q=aexp(-z/b), the coefficient a has an apparent power function correlation with sediment transport rate and increases simultaneously with wind velocity, but there is no clear correlation between them. The coefficient b has no significant correlation with these two factors. At the brink-line, the profiles were segmented at the 0.10 m height: the profiles of near surface follow exponential decay while the upper layers obey power function.

Key words: parabolic dune, aeolian sediment flux profile, function fitting, Hobq Desert